742例原发性IgA肾病患者的临床病理特征及其预后分析

Analysis of the clinicopathological characteristics and prognosis of 742 cases with primary IgA nephropathy

目的探讨原发性IgA肾病(IgA nephropathy,IgAN)患者的临床病理特征及IgAN患者肾脏预后的影响因素。方法回顾性分析2015年1月至2019年9月在安徽医科大学第一附属医院经肾活检确诊原发性IgAN的患者资料,并根据肾活检时基线肾功能(estimated glomerular filtration rate,eGFR)水平分为A组[eGFR≥90 ml·min^(-1)·(1.73 m^(2))^(-1)]、B组[eGFR 61~89 ml·min^(-1)·(1.73 m^(2))^(-1)]和C组[eGFR≤60 ml·min^(-1)·(1.73 m^(2))^(-1)],比较3组患者的临床及病理特征。采用Kaplan-Meier法估计肾脏累积生存率,采用Cox比例风险回归模型分析IgAN患者肾脏预后的影响因素。结果共742例患者被纳入本研究,男性325例(43.8%),女性417例(56.2%),肾活检时中位病程为6(1,24)个月,中位年龄为36岁(18~68岁),其中A组394例(53.1%)、B组203例(27.4%)和C组145例(19.5%)。随着基线肾功能水平降低,患者合并肾病综合征、高血压、贫血、高尿酸血症的比例及尿蛋白量、血三酰甘油、血总胆固醇水平明显增加,而肉眼血尿发作史的比例和血清白蛋白-球蛋白比值明显降低(均P<0.05)。在病理资料比较中,毛细血管内细胞增生、节段性硬化或粘连、肾小管萎缩或间质纤维化、球性硬化、肾小动脉管壁增厚及玻璃样变、Lee氏分级Ⅳ和Ⅴ级的比例随着基线肾功能下降而增加(均P<0.05)。Kaplan-Meier生存曲线分析提示,随着基线肾功能下降,肾脏累积生存率呈现下降趋势(Log-rank检验χ^(2)=88.510,P<0.001)。多因素Cox回归分析提示起病时表现为肾病综合征(HR=2.399,95%CI 1.054~5.459,P=0.037)、高血压(HR=1.806,95%CI 1.071~3.048,P=0.027)、基线肾功能下降(以A组为参照,B组:HR=2.383,95%CI 1.053~5.392,P=0.037;C组:HR=6.878,95%CI 3.074~15.393,P<0.001)、病理表现为伴IgG沉积(HR=2.224,95%CI 1.384~3.574,P=0.001)、球性硬化(HR=2.075,95%CI 1.230~3.501,P=0.006)是IgAN患者肾脏不良预后的影响因素。结论IgAN患者基线肾功能水平可用于预测患者临床和肾脏病理损伤程度,起病时表现为肾病综合征、高血压、基线肾功能下降、伴IgG沉积、球性硬化是IgAN患者肾脏不良预后的独立影响因素。

Objective To investigate the clinicopathological characteristics and influencing factors of kidney prognosis in primary IgA nephropathy(IgAN)patients.Methods The data of primary IgAN patients diagnosed with renal biopsy in the First Affiliated Hospital of Anhui Medical University from January 2015 to September 2019 were retrospective analyzed.According to the level of baseline estimated glomerular filtration rate(eGFR)when performing renal biopsy,the patients were divided into group A[eGFR≥90 ml·min^(-1)·(1.73 m^(2))^(-1)],group B[eGFR 61-89 ml·min^(-1)·(1.73 m^(2))^(-1)]and group C[eGFR≤60 ml·min^(-1)·(1.73 m^(2))^(-1)].The clinical and pathological data were collected and compared among the three groups.Kaplan-Meier method was conducted for renal results,whereas the Cox proportional-hazards regression model was exploited to analyze the influencing factors of kidney prognosis in IgAN patients.Results A total of 742 patients were included in the study,including 394 cases(53.1%)in group A,203 cases(27.4%)in group B,and 145 cases(19.5%)in group C.There were 325 males(43.8%)and 417 females(56.2%).The median duration of renal biopsy was 6(1,24)months,and the median age was 36 years old(18-68 years old).As the baseline level of renal function decreased,the proportion of patients with nephrotic syndrome,hypertension,anemia and hyperuricemia and the levels of 24 h urinary protein,serum triglyceride and total cholesterol increased significantly(all P<0.05),while the proportion of gross hematuria episodes and the ratio of serum albumin to globulin significantly decreased(all P<0.05).For the aspect of pathological manifestations,the proportions of cell proliferation in capillaries(E1),segmental sclerosis or adhesion(S1),renal tubular atrophy or interstitial fibrosis(T1/2),globular sclerosis,renal arteriole wall thickening and vitreous degeneration,Lee's gradeⅣandⅤincreased with the decrease of baseline renal function(all P<0.05).Kaplan-Meier analysis showed that the cumulative renal survival rate decreased with the decline of baseline renal function(Log-rankχ^(2)=88.510,P<0.001).As a result of multivariate Cox regression analysis,nephrotic syndrome(HR=2.399,95%CI 1.054-5.459,P=0.037),hypertension(HR=1.806,95%CI 1.071-3.048,P=0.027),low baseline eGFR(taking group A as the reference,group B:HR=2.383,95%CI 1.053-5.392,P=0.037;group C:HR=6.878,95%CI 3.074-15.393,P<0.001),IgG deposition(HR=2.224,95%CI 1.384-3.574,P=0.001)and globular sclerosis(HR=2.075,95%CI 1.230-3.501,P=0.006)were the independent influencing factors for renal progression in primary IgAN patients.Conclusions The level of baseline renal function in primary IgAN patients can be used to predict the extent of clinic-pathological damage.Nephrotic syndrome,hypertension,low baseline eGFR,IgG deposition and globular sclerosis are the independent influencing factors for renal progression in primary IgAN patients.